Hello @haofengli2-c ...
You will probably need to speak to your school's local Canvas administrator or someone at your school's Online Learning / eLearning department so that they can drop / unenroll you from that course in Canvas. We here in the Community wouldn't be able to help you with that since we only have access to our own Canvas environments. Hopefully, someone at your school will be able to assist you with your question. Good luck to you!
